Improvement in machines for sewing boots and shoes



G.- McKAY.

MACHINES FOR SEWING BOOTS AND SHOES.

No.188,809. Patented March 27,1877.

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'LP'ETEIS. PHOTD-UTHOGRAPHER, WASHINGTON. D C.

PATENT Qrrron GORDON MQKAY, oF. CAMBRIDGE, MASSACHUSETTS.

I-MPRQVEJMVEVNTJN MACHINES FOR SEWING BOOTS AND SHOES.

Specification forming part of Letters :Patent No. 188,809, dated March27, 1877; application tiled- October 18, 1876.

State of Massachusetts, have invented-.anllmproved Sewing-Machine, ofwhich the following is a specification This invention relates tosewing-machines for sewing or uniting the soles to-uppers in themanufacture of boots and shoes.

- In the machine described in United States Patent No, 36,163, provisionis-rnade for lifting the presser fromavariable base-line, awhich is thesurface of the #stock on which it rests when down, and then to penmititto'des'eend upon thesurface of the stock. The-machine also describesmechanism for operating the needle to cause it to -aut0matically vary:its

throw according to thethickness of the-stock. The needle-lever iscarried by an adjustable fulcrum bar or post, the position of which isdetermined by the thickness of the stocknpon which the .presser :rests,an -arm projecting from the fulcrum-post resting upon a,.-Iu'g or,

projection located bytheposition ofithefpresser, the latter resting uponthe work.

In the machine to be herein,described,lthe needle, cast-0tt', whirl,&c., constituting the sewing parts, and thefeed, are or maybeconstructed the same as described in such patent, and in Patent N 0.45,422, to both of which reference may be had. I

In this present inventionthepresser-foot is stationary instead ofmovable' asin such patents, and the hornis adapted to fall adetermineddistance from a variable base-line, represented by the inner portion ofthe shoe being sewed. The needle is always lifted a certain distanceabove the surface of the stock, the upward position of which isdetermined by the rigid presser, and the extreme downward throw of theneedle is made variable according to the variation in the thickness ofthe stock, and so that the hook of the needle will-be brought to aproper position with relation to the whirl in the horn, to be suppliedwith thread, notwithstanding the variations in the position of the hornby reason of the variations in the stock.

Figure 1 represents, in side elevation, sufficient of a well-knownMcKaysewing-machine to show how this invention may be embodied therewith; andFigs. 2, 3, and 4 are details of the devices for depressing thehorn-shaft, and for lockin g it to resist the thrust of the needle.

The main shaft on has a disk provided with a cam-groove, b, to move thelink a, connected with the needlelever 01, having its fulcrum, at e, ona movable fulcrum-post, f, the downward position of which is regulatedby means of an adjustable collar, g, that meets the plate h,

.the collar resting upon the plate when the needle-bar is being lifted,to draw the needle from the upper side of the Work, this insuring thelifting of the needle to a certain defined position above the top of thework, or

.the bottom of the fixed presser, thereby forming loops of equal lengthat each stitch, and by moving the collar the length of loop may bechanged. The needle-bar i is connected with the lever d. A secondcam-groove, j, in the face of a cam-disk, It, operates an elbowlever, Z,pivoted at m, the lever being suitably connected with the pawl-carriagen, which is a loose collar surrounding the horn shaft 0, and providedwith pawls pp, that are held up in griping contact with the horn shaftby springs q. The foot-plate r, fixed to the hornshaft, serves thepurpose of a base or foot, and

bears upon a rest, it, preferably provided with rollers s, the restbeing adapted to be held or fixed in position when the horn is to belocked,

to hold the work between it and the rigid .presser against the thrustot'the needle. The rest t, free to be moved upon the horn-shaft, isconnected with a fulcrum-post stop-lever, u, pivoted at 'v, the rest andstop-lever u being lifted by means of a spring, w, that bears againstthe cam-sleeve m of the rest. This spring to is of sufficient strengthto overcome the weight of the horn and its appendages, and to lift itwhen the pawls are freed from the horn-shaft, in order to cause theupper end .of the born to press upward against the inner side of theshoe.

The upper end of the horn is pressed against the under or inner side ofthe work, and is locked in position by the cam projections on a cam,01,, in this instance formed upon a sleeve, 12, Surrounding thehornshaft, an arm projecting from the sleeve being connected, by link 0,with a lever, d, operated by cam k, a spring, e, moving the cam-sleeveand link 0 in the opposite direction. Prior to locking the horn it isheld up by the spring to, causing the stock to be clamped between itsupper end 9' and the lower end of the stationary presser f, the rest t,with the stop-lever it, being also held up by this spring, therebyinsurin g the proper relative positions of the end of the horn and thefulcrum-post stop-lever to. In this condition the horn is locked, andthe cam b commences to move the need e-lever d; but the needle does notmove until the adjusting-screw h, or a part of the rising fulcrum-post,meets the fulcrum-post stop-lever u, at which time, the fulcrum-postbeing fixed, the needle-lever commences to descend. The

position of the stop-lever u is, it is seen, de-

termined by the position of the horn, and, consequently, the thicknessof the stock.

After the needle penetrates the stock the cam portion a of thecam-sleeve b releases the rest and the horn from pressure, except thatof the spring w. The movement of shaft or continuing, the fulcrum-postis caused to descend until the collar 9 is seated, and then the needlecommences to rise. At this time the pawl-carriage, operated upon by thelever -l, is moved down, the pawlsp on the carriage engaging andcarrying with it the horn, moving it down always a certain distance fromthe under side of the work, where it rested being also lifted at thesame time by the lever but the spring cannot lift the horn above the.

position from which it was taken by the pawlcarriage at its last descentuntil after the pawls are tripped by the adjustable tripping devices3 3.The tripping devices will trip the pawls, if the stock is thinner thanat the points where the needle last penetrated it, and then thehorn-shaft, disengaged from the pawls, will be lifted by the spring tountil the upper end of the horn bears against the work. The rollers sare to overcome friction between the plate 1' of the horn-shaft and thercstt when the horn is rotated in the usual way.

The cam for locking the horn in position may be constructed differentlyfrom the cam shown in' the drawing, and it may be operated at the propertime from any moving part of the machine without departing from thisinvention.

The screw h is to assist in adjusting the hook of the needle in properrelation to the whirl.

I claim- 1. In a sewing-machine, the combination, with a stationarypresser and a horn, of mechanism adapted to automatically lower the hornfrom a variable base-line, the lower surface of the stock being sewed,substantially as described.

2. A horn and attached foot-plate, 'r, in combination with a rest, andmechanism to lock the horn and rest, and with a fulcrum-post stop-lever,all substantially as described.

3. In combination, a horn and mechanism to depress it from-a variablebase-line, corresponding with the under side of the stock, and afulcrum-post stop-lever to determine the descent of the needle,substantially as described. i

4. The needle-actuating lever and fulcrumpost, in combination with acollar to determine its downward throw, and a fulcrum-post stop-leverplaced imposition by the born to determine its upward throw,substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

GORDON MOKAY.

Witnesses:

G. W. GREGORY, S. B. KIDDER.

